The Optimization Of Oil-gas-water Treating Facility On Offshore Platform

Oil-gas processing system is an indispensable link of the oil industry chain.However,compared with onshore oil production,there are numerous potential risks existing in offshore oil-gas processing system.For instance,severe slug tends to occur in the riser of a production platform,which may leads to liquid level oscillation in the separator installed on the platform,affecting its performance;The platform may vibrate due to the wind,current and waves,resulting in an adverse working condition for separator.In addition,the nature frequencies of separator are very close to the vibration frequency of platform,which can cause sloshing.Because of the limitation of experiment,the work in this dissertation mainly fulfilled with the help of numerical simulation.The study focused mainly on two aspects.For one thing,the simulations of severe slug were accomplished using OLGA,and an efficient way were proposed to control severe slug.For another,the sloshing regularity and sloshing suppression strategies were studied.In detail,nature frequencies of liquid and platform vibration were calculated by ANSYS,then sloshing and its suppression were studied by FLUENT combining with UDF.The study showed that: The occurrence of severe in riser can cause violent liquid level oscillation,affecting the performance of separator.By comparing various severe slug control methods,it is found that PID auto-control is an efficient way,and it is highly recommended;By comparing the nature frequencies results of ANSYS and FLUENT with analytic results,the accuracy of ANSYS and FLUENT are validated,which can meet the demand of engineering;The simulation of sloshing with the help of FLUENT indicates that the sloshing are most violent in a-year working condition.The water spill over the weir and flow in to oil chamber.The layout that the longitudinal axis is perpendicular to the wave direction has the slightest sloshing.The analysis of fluid and structure interaction illustrates the internal components are in the state of alternating stress,with the potential risk of fatigue failure;By the optimization of the structural geometries and layout of internal components,the maximum of sloshing suppression is achieved,which is up to 87%;...